parkverbot

Modern rotational hard disks have a misfeature involving the regular automatic unloading of the heads, measurable by the SMART attribute "Load_Cycle_Count", that causes latency on wake-up, and while the manufacturers sell this as "green", it is believed to cause reduced hard disk life.

The parkverbot daemon will periodically issue small read requests in order to keep the hardware from going to its head-unloaded idle state.